Marine engines have a drive shaft that turns the propeller. The end of the propeller drive shaft remote from the propeller is connected to the gear assembly that effects the rotation of the propeller drive shaft. The gear assembly and propeller drive shaft are contained within a housing. In order to position the propeller drive shaft in the center of the housing, a bearing carrier is press fit into the housing that surrounds the propeller drive shaft.
In the event of gear assembly damage or in the event that routine maintenance is needed, it is necessary to remove the bearing carrier from the housing. This allows access to the gear assembly inside the housing for repair or maintenance.
Because the bearing carrier is tightly press fit into the housing, it is not possible to remove the bearing carrier by hand; a tool must be used to pull the bearing carrier out of the housing. It is desirable to remove the bearing carrier without damaging it so that the bearing carrier may be reused to center the propeller drive shaft when the gear assembly is reassembled inside the housing. Bearing carriers are quite expensive, costing as much as $200.00 and up. Breaking or destruction of the bearing carrier during maintenance or repair of the gear assembly is an unnecessary expense that the boat owner does not like to incur.
The bearing carrier has a central hollow shaft through which is disposed the propeller drive shaft. The bearing carrier also has an outer ring member that positions the bearing carrier in the center of the housing. A plurality of radially extending spokes connect the outer ring member to the central hollow shaft. If force is applied to the outer ring member to remove the bearing carrier from the housing, the outer ring member is prone to break off from the central shaft and the spokes. The design of the outer ring member portion of the bearing carrier will not accommodate the pulling force necessary to overcome the press fit of the bearing carrier in the housing.
One type of tool to pull the bearing carrier from the gear housing has been distributed by Mercury Marine, a division of the Brunswick Corporation, Fond du Lac, Wis. The tool utilizes a pair of puller jaws (Mercury Model No. C-91-46086A1) along with a puller bolt (Mercury Model No. C-91-85716). Each puller jaw has a J-shaped foot that hooks around the underside of the outer ring of the bearing carrier. The puller bolt is positioned against the end of the propeller drive shaft and as the puller bolt is turned down against the propeller drive shaft, the puller jaws move the bearing carrier in a direction opposite to the direct of the force of the puller bolt, thereby removing the bearing carrier from the housing.
The Mercury Marine tool has the disadvantage that each of the feet on the end of the puller jaws turn outward and hook under the outer ring on the bearing carrier. Thus all of the pulling force of each puller jaw is transmitted onto the outer ring of the bearing carrier. It is quite easy for the puller jaws to slip off these bosses thereby preventing removal of the bearing carrier from the housing. It is also quite easy for the outer ring to break away from the body of the bearing carrier thereby preventing reuse of the bearing carrier. In fact, the repair manual distributed by Mercury Marine cautions against using the puller tool by pulling on the bearing carrier outer ring, but the repair manual does not indicate where the puller tool's jaws are supposed to be positioned if they are not positioned on the outer ring of the bearing carrier.
Another type of tool used to pull bearing carrier from the housing is distributed by Outboard Marine Corporation of Waukegan, Ill. This tool is designed for the bearing carriers used in the marine engines made by Outboard Marine Corporation. This tool utilizes a pair of J-shaped feet that dangle loosely from a mounting bracket that is designed to go on the end of a drive shaft. Another version of the puller tool made by Outboard Marine Corporation has legs that screw into threaded apertures on the bearing carrier itself. Both of these tools require the mechanic to use both of his hands simultaneously to remove the bearing carrier.
It is an object of the present invention to provide an improved bearing carrier puller tool that transmits the pulling force directly onto the spokes connecting the outer ring to the central hollow shaft and not onto the outer ring itself.
It is a feature of the present invention to provide a specially designed foot on the end of the puller jaw so that orientation of the foot in the space between the outer ring and the central hollow shaft of the bearing carrier will secure the foot to the bearing carrier so that when the pulling force is applied to the tool the bearing carrier will easily and effectively removed from the housing.
It is an advantage of the present invention that the puller tool will remove the bearing carrier from the housing efficiently and quickly and the risk of premature separation of the puller tool from the bearing carrier will be eliminated as well as the risk of breaking of the bearing carrier due to the separation of the outer ring from the bearing carrier.